1. Field of the Invention
The present invention relates to an angular velocity sensor used, for example, for detecting motion blurring of a video camera, detecting a motion in a virtual reality device, detecting a direction in a car navigation system, and the like. Specifically the invention relates to a method for manufacturing a small vibrating gyrosensor and a vibrating element each including a cantilever vibrator.
2. Description of the Related Art
As consumer angular velocity sensors, so-called vibrating gyrosensors are widely used, in each which a cantilever vibrator is vibrated at a predetermined resonance frequency, and Coriolis' force produced by the influence of an angular velocity is detected by a piezoelectric element to detect the angular velocity.
The vibrating gyrosensors have the advantages of a simple mechanism, a short starting time, and a low manufacturing cost. For example, vibrating gyrosensors are mounted on electronic devices, such as a video camera, a virtual reality device, and a car navigation system, for detecting motion burring, an operation, and a direction, respectively.
A usual vibrating gyrosensor includes a vibrating element which is manufactured by machine-cutting an appropriate piezoelectric material to form a predetermined shape. A vibrating gyrosensor is required to have a smaller size and higher performance with reduction in size and weight and increases in functionality and performance of a main body device on which vibrating gyrosensor is mounted. However, it has been difficult to manufacture a small vibrating element with high precision due to the limit of machining precision.
Therefore, there has recently been proposed a vibrating gyrosensor including a cantilever vibrating element formed by laminating a pair of electrode layers with a piezoelectric thin film layer provided therebetween on a silicon substrate using a thin film technique for semiconductor processes (refer to, for example, Japanese Unexamined Patent Application Publication No. 7-113643). Such a gyrosensor may be reduced in size and thickness and thus complexed or increased in functionality by combination with a sensor for other purposes.